PONG for ComputerCraft

--Vars
width, height = term.getSize()
i = 0
i_max = width*height
x = 1
y = 1
p1 = 0
p2 = 0
pad1 = math.ceil(height/2)
pad2 = math.ceil(height/2)
up = false
right = true

--Functions
function drawPads()
    term.setCursorPos(1,pad1-1)
    write("#")
    term.setCursorPos(1,pad1)
    write("#")
    term.setCursorPos(1,pad1+1)
    write("#")
    term.setCursorPos(1,pad1-2)
    write(" ")
    term.setCursorPos(1,pad1+2)
    write(" ")
    if pad1 == 4 then
        term.setCursorPos(1,pad1-2)
        write("-")
    end
    if pad1 == 15 then
        term.setCursorPos(1,pad1+2)
        write("-")
    end

    term.setCursorPos(width-1,pad2-1)
    write("#")
    term.setCursorPos(width-1,pad2)
    write("#")
    term.setCursorPos(width-1,pad2+1)
    write("#")
    term.setCursorPos(width-1,pad2-2)
    write(" ")
    term.setCursorPos(width-1,pad2+2)
    write(" ")
    if pad2 == 4 then
        term.setCursorPos(width-1,pad2-2)
        write("-")
    end
    if pad2 == 15 then
        term.setCursorPos(width-1,pad2+2)
        write("-")
    end
end

function ball()
    term.setCursorPos(x,y)
    write(" ")
    if up == true then
        y = y - 1
    else
        y = y + 1
    end
    if right == true then
        if (x == width - 2) then
            if y == pad2 or y == pad2-1 or y == pad2+1 then
                x = x - 1
                right = false
            elseif up == true and y == pad2-2 then
                x = x - 1
                right = false
            elseif up == false and y == pad2+2 then
                x = x - 1
                right = false
            else
                x = x + 1
            end
        else
                x = x + 1
        end
    else
        if (x == 2) then
            if y == pad1 or y == pad1-1 or y == pad1+1 then
                x = x + 1
                right = true
            elseif up == true and y == pad1-2 then
                x = x + 1
                right = true
            elseif up == false and y == pad1+2 then
                x = x + 1
                right = true
            else
                x = x - 1
            end
        else
            x = x - 1
        end
    end
    if x == 1 then
        right = true
        p2 = p2 + 1
        x = math.ceil(width/2)
        y = math.ceil(height/2)
        term.setCursorPos(math.ceil(width/2)-3,1)
        write(p1.." | "..p2)
    end
    if x == (width - 1) then
        right = false
        p1 = p1 + 1
        x = math.ceil(width/2)
        y = math.ceil(height/2)
        term.setCursorPos(math.ceil(width/2)-3,1)
        write(p1.." | "..p2)
    end
    if y == 3 then up = false end
    if y == height-2 then up = true end
end

--Intro
term.clear()
term.setCursorPos(1,1)
print("")
print("")
print("     X==---------------------------------==X")
print("     |ComputerCraft Pong, made by Chub1337!|")
print("     X==---------------------------------==X")
print("")
print("")
print("")
print("       Player 1 controls: W = up, S = down")
print("")
print("       Player 2 controls: O = up, L = down")
print("")
print("")
print("")
print("")
print("")
print("")
write("Press <Enter> to continue.")
io.read()

term.clear()
term.setCursorPos(1,1)

write("Player 1")
term.setCursorPos(width-8,1)
write("Player 2")
term.setCursorPos(math.ceil(width/2)-3,1)
write(p1.." | "..p2)
drawPads()
term.setCursorPos(1,height)
write(pad1.."|"..pad2)

for i=1,width-1,1 do
    term.setCursorPos(i,2)
    write("-")
end
term.setCursorPos(1,height-1)
for i=1,width-1,1 do
    term.setCursorPos(i,height-1)
    write("-")
end

--Pong
x = math.ceil(width/2)
y = math.ceil(height/2)
dir = math.ceil(math.random(0,4))


if dir == 1 then
    up = true
    right = true
elseif dir == 2 then
    up = true
    right = false
elseif dir == 3 then
    up = false
    right = true
elseif dir == 4 then
    up = false
    right = false
end

function timerupdate()
    ball()

    term.setCursorPos(7,height)
    write("X:"..x.." ")
    term.setCursorPos(13,height)
    write("Y:"..y.." ")
    term.setCursorPos(18,height)
    write("up:"..tostring(up).." ")
    term.setCursorPos(30,height)
    write("right:"..tostring(right).." ")
    term.setCursorPos(x,y)
    write("O")
    term.setCursorPos(1,height)
    write(pad1.."|"..pad2.." ")
        timer1 = os.startTimer(.1)
end
timer1 = os.startTimer(.1)
while true do
    event, par = os.pullEvent()
    if event == "timer" and par == timer1 then timerupdate() end
    if event == "char" then
        if par == "w" then
            pad1 = pad1 - 1
            if pad1 < 4 then
                pad1 = 4
            end
        elseif par == "s" then
            pad1 = pad1 + 1
            if pad1 > height-3 then
                pad1 = height-3
            end
        end
        if par == "o" then
            pad2 = pad2 - 1
            if pad2 < 4 then
                pad2 = 4
            end
        elseif par == "l" then
            pad2 = pad2 + 1
            if pad2 > height-3 then
                pad2 = height-3
            end
        end
    end
    drawPads()
end